The inventive concept herein relates to data storage systems, and more particularly, to data storage systems using methods of transmitting failed addresses in order to reduce the number of read requests during a rebuild operation of a redundant array of independent disks (RAID).
RAID devices including a plurality of drives corresponding to hard disk drives (HDDs) or solid-state drives (SSDs), have been used to redundantly store data. In the event that one driver in a RAID device fails, the stored data may still be retained in other drives of the RAID device.
Upon failure of a drive in a RAID device, a RAID rebuild operation may be performed to exchange the failed drive in the RAID device with a new drive. In a RAID rebuild operation, a host may perform a data rebuild operation on the entire failed drive. In such a case, rebuild time may be lengthy.
On the other hand, in some RAID rebuild operations the host may perform a rebuild operation only on data in a failed portion of the failed drive. In this case, when the failed drive includes a plurality of failed portions, the failed drive may terminate a data read operation requested by the host whenever the failed drive accesses a failed logical block address (LBA) of the failed portion. The host may then issue a read request for a next LBA to the failed drive. However, if a number of failed LBAs in the failed drive is in a read request range set in the host, the host may issue several read requests because the failed drive interrupts read operations due to the failed LBAs.